Optical slave help

Just got one of those optical slave triggers from ebay. It can trigger the flash only once then I have to remove and put the flash back on again so it will work.

I'm sure its supposed to trigger the flash everytime it senses another flash.

What am I doing wrong?

In general optical slaves just do not work with Canon EX flash units. You get one flash then lockup as you cite in your post.

Optical slaves work with almost all flash units, including older Canon flash series like the EZ, but not the EX series.

The exception is 580EX II, but the optical slave must be connected the the PC port on the 580EX II. If you connect the optical slave to the hotshoe on the 580EX II it is just as uncooperative as any other EX flash unit.

There are scores of threads about this issue on this forum.

Enjoy! Lon

Yep.

Plug it into the PC socket on your 580EX II and it will work fine. If the slave you have doesn't have a PC connector, go to http://flashzebra.com and he'll fix you up.

Thanks Lon,

I'm also using it on an old sunpak 333 flash and it does the same. I even butchered it and connected the 2 wires to a 2.5mm mono plug and connected to my modded sunpak but still does the same.

I guess any brand will not cooperate with my ex flash so I'm steering away from them for now.

Now back to my poverty wizards.

Edit:

@Curtis - Thyanks. I'm a lurker on that site.

Does anyone offer an explanation for this?

An optical slave is pretty simple. It just senses a flash of light and completes a little circuit on the flash's hotshoe. Why can't the flash fire every time?

I just tried my 580EX II and it will fire repeatedly just by touching the center contact to the metal hotshoe. No problem at all.

So why should an optical slave be any different? Maybe the circuit in the optical slave is the problem. Not the flash.

strobe monkey wrote in post #6282336
Thanks Lon,

I'm also using it on an old sunpak 333 flash and it does the same. I even butchered it and connected the 2 wires to a 2.5mm mono plug and connected to my modded sunpak but still does the same.

I guess any brand will not cooperate with my ex flash so I'm steering away from them for now.

Now back to my poverty wizards.

Edit:

@Curtis - Thyanks. I'm a lurker on that site.

My guess is you have the polarity backwards on the 333.

You should have no problems with a functioning optical slave and the Sunpak 333, unless you have the polarity wired backwards.

Polarity matters.

The flash sync circuit powers the optical slave circuit, so the circuit will not work if the polarity is backwards. Jut like if you put your AA cells in backwards in your 580EX II, you would not expect function.

Enjoy! Lon

msowsun wrote in post #6282348
Does anyone offer an explanation for this?

An optical slave is pretty simple. It just senses a flash of light and completes a little circuit on the flash's hotshoe. Why can't the flash fire every time?

I just tried my 580EX II and it will fire repeatedly just by touching the center contact to the metal hotshoe. No problem at all.

So why should an optical slave be any different? Maybe the circuit in the optical slave is the problem. Not the flash.

There are scores of posts on this issue in this forum.

But, optical slaves work with almost all flash units, but will not work with Canon EX flash units, so I would cite the issue with the Canon EX flash units (not the optical slaves) - even though you can possibly make the EX flash units work with a more specialized optical slave circuit.

Enjoy! Lon

FlashZebra wrote in post #6282399
My guess is you have the polarity backwards on the 333.

You should have no problems with a functioning optical slave and the Sunpak 333, unless you have the polarity wired backwards.

Polarity matters.

The flash sync circuit powers the optical slave circuit, so the circuit will not work if the polarity is backwards. Jut like if you put your AA cells in backwards in your 580EX II, you would not expect function.

Enjoy! Lon

I did check the polarity, red wire from the optical slave is connected to the middle of the hotshoe and green wire to the ground - and I followed that on the mono plug. Polarity on the modded flash is also observed.

As I've said, it works but then locks up just like what it does with the 580.

This really makes me hate Canon and thinking of going Nikon

I have an optical slave. His name's Mike, he's a deaf mute. I employ him to do my cleaning, prepare my meals, and answer the phone - he just picks it up and screams, which is great for telemarketers. If it's important they call back on my cell. I call him my optical slave because since he can't hear me I have to give him his instructions in writing. I use an etch-a-sketch.

msowsun wrote in post #6282348
Does anyone offer an explanation for this?

An optical slave is pretty simple. It just senses a flash of light and completes a little circuit on the flash's hotshoe. Why can't the flash fire every time?

I just tried my 580EX II and it will fire repeatedly just by touching the center contact to the metal hotshoe. No problem at all.

So why should an optical slave be any different? Maybe the circuit in the optical slave is the problem. Not the flash.

Actually, it's the combination of both the optical slave and the flash since some optical triggers will work with the EX flashes. But it's mostly the design of the EX flashes that makes it fail to work with the majority of the optical triggers out there.

More details here:

https://photography-on-the.net …php?p=1530948&p​ostcount=2